Spinal Deformity, Dorsal Kyphosis and Bone Mineral Density

It has been show that spine deformity index is a better indicator of the functional capacity of the osteoporotic patient than the number of vertebral fractures. In order to investigate the relation between spinal deformity, dorsal kyphosis and the bone mineral density, we undertook the following study. In 40 postmenopausal women (age 59,1±7) spine deformity index (SDI) was calculated by lateral roentgenograms of the dorsal and lumbar spine. 25 subjects at premenopausal age were also x-rayed to find the normal limits. Dorsal kyphosis (DK) was measured by Cobb’s angle. Bone mineral density (BMD) of the lumbar spine and proximal femur were measured by DEXA. Pearson’s correlation coefficient and Student’s t-test were used as statistical analysis. The results show that there was a significant correlation between DK and SDI. BMD's at femoral neck and lumbar spine were not correlated with DK and SDI (p>0,05). In patients with <40 degrees of DK, BMD’s of the two regions, t and z scores were higher than those with Cobb’s angle >40 degrees. The difference was not significant. We conclude that as the spinal deformity increases, DK is expected to increase and BMD is expected to decrease